Highspeed Board Design

[rocker1025]

What does mean by high speed board design? Please any explain me about this subject...

Thank You
rocker1025

 

[praveenlb]

High speed board consist of digital, analog ,and mixed signal.where flow of the signals are in nano second..example DDR Routing , RF section..clock signal
..
Regards
praveen Bhat

---------- Post added at 14:29 ---------- Previous post was at 14:17 ----------

 

[rocker1025]

Thank u so much praveen

 

[boldstone]

When frequency is exceeded and enters to high frequency range the reaction of device and PCB object is changed. In high frequency the traces is not just a conductor with constant low resistance.
It will be a RLC. it means, traces act as inductor & capacitor. Due to the capacitance & inductance is depending on frequency too.
Xc=1/2*pi*f*C and Xl=2*pi*f*L
Xc: capacitive reactance
Xl: Inductive reactance
pi: 3.1415
f: frequency
c: trace capacitance
l: trace inductance

for Exp.: f= 250 MHz, L=50 nH ==> Xl=78.5 OHM !!
As you see, the trace is not just a conductor in high frequency.
It was just one of the phenomenons on the high frequency range! There are several undesirable phenomenons will be happen. They must be eliminated by designers.
So it is vital to consider several guide lines to make a PCB that works in high frequency range safely & reliably.
This guide lines have 3 main duties:
1- Make a PCB that works smoothly!
2- Signal integrity
3- Meet EMC directive